The pKa's of different kinds of thiols (R-SH) were investigated by using the M06-2X method with a SMDsSAS model.

We propose and numerically demonstrate a design of bidirectional transverse electric (TE) polarized mode-order converter based on silicon-on-insulator platform. This converter is realized by introducing high refractive index material inlaid in a silicon slab waveguide. Simulated by three-dimensional finite-difference time-domain method, the forward (TE0 to TE1-like conversion) transmittance reaches approximately 88.2%, while the backward value (TE1 to TE0-like conversion) is about 89.4% at the wavelength of 1550 nm. The footprint of this converter is as small as 0.95 × 1.5 μm 2. Fabrication tolerance analysis demonstrates satisfactory robustness. Moreover, we present a polarization-independent converter with slightly modified geometry. The transmittance keeps above 87.2% within the wavelength range from 1500 nm to 1600 nm for both TE and transverse magnetic modes. These devices are expected to contribute to the on-chip mode division multiplexing.

In this work, we introduce Ni nanopyramid arrays (NPAs) supported amorphous Ge anode architecture and demonstrate its effective improvement in sodium storage properties. The Ni−Ge NPAs are prepared by facile electrodeposition and sputtering method, which eliminates the need for any binder or conductive additive when used as a Na‐ion battery anode. The electrodes display stable cycling performance and enhanced rate capabilities in contrast with planar Ge electrodes, which can be owing to the rational design of the architectured electrodes and firm bonding between current collector and active material (i. e. Ni and Ge, respectively). To validate improvement of nanostructures on electrochemical performance, sodium insertion behavior of crystalline Ge derived from Mg 2 Ge precursor has been investigated, in which limited but effective enhancement of sodium storage properties are realized by introducing porous nanostructure in crystalline Ge. These results show that elaborately designed configuration of Ge electrodes may be a promising anode for Na‐ion battery applications.

The hydrazine derivatives have been regarded as the important building blocks in organic chemistry for the synthesis of organic N-containing compounds. It is important to understand the structure-activity relationship of the thermodynamics of N-N bonds, in particular, their strength as measured by using the homolytic bond dissociation enthalpies (BDEs). We calculated the N-N BDEs of 13 organonitrogen compounds by eight composite high-level ab initio methods including G3, G3B3, G4, G4MP2, CBS-QB3, ROCBS-QB3, CBS-Q, and CBS-APNO. Then 25 density functional theory (DFT) methods were selected for calculating the N-N BDEs of 58 organonitrogen compounds. The M05-2X method can provide the most accurate results with the smallest root-mean-square error (RMSE) of 8.9 kJ/mol. Subsequently, the N-N BDE predictions of different hydrazine derivatives including cycloalkylhydrazines, N-heterocyclic hydrazines, arylhydrazines, and hydrazides as well as the substituent effects were investigated in detail by using the M05-2X method. In addition, the analysis including the natural bond orbital (NBO) as well as the energies of frontier orbitals were performed in order to further understand the essence of the N-N BDE change patterns.

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